Stabilizing device



p 1 M. I GIANOLIY 2,174,225

STABILIZING DEVICE Filed Ndv. 24, 1957 2 Sheets-Sheet 1 INVENTOR: MARCEL LOUIS GIANOLJ MW, $104+ QT ATTORNEY5 Sept. 26, 1939. GIANQL] 2,174,225

STABILIZING DEVICE Filed Nov. 24, 1937 2 sheets-sheet 2 FIG? Fi .6

400 L..& f a C- E 1 I'NVENTOR mma 1.00/5 adv/v01 ATTORN E75 Patented Sept. 26, 1939 UNITED STATES PATENT; OFFICE.

5 Claims.

The present invention relates to automatic stabilizing devices for aerial or marine movable objects, composed of a main surface pivoted on the body of the movable object, of an auxiliary surface pivoted on the main surface, and of a kinematic connection between the auxiliary surface and the body of the movable object compelling said auxiliary surface to modify its position relatively to the main surface when the latter itself modifies its position relatively to the body of the movable object.

It is. advantageous for stabilizing devices of this kind which operate according to the modifications in direction of the wind or relative stream, to be placed at the rear of the movable object; this arrangement, in fact, automatically ensures the damping of the oscillations of the movable object. But it is then necessary that the stabilizing device should be devised in such a manner that achange of direction (or rotaticn). of the relative wind causes the main surface to rotate in reverse direction to said rotation of the relative wind, for increasing the reaction produced by the relative wind on said surface. Now, up to the present moment, in stabilizing devices which satisfy this condition, the auxiliary surface is placed in front of the main surface, which, for that purpose, is provided with arms supporting at the front the pivot of the auxiliary surface. The invention is adapt ed to provide a stabilizing device of the same kind, but moresimple, lighter and stronger, in which the auxiliary surface is pivoted at the rear of the main surface.

Stabilizing devices indeed exist in which the auxiliary surface is pivoted at the rear of the main surface; but these known devices, under the effect of a rotation of the relative wind, rotate in the same direction as said rotation of the relative wind instead of rotating in reverse direction, as in the devices to which the invention relates. a

The invention is characterized by the fact that the pivot of the main surface is located behind its center of thrust and the pivot of the auxiliary surface behind the main surface, whilst the kinematic connection between the body of the movable object and said auxiliary surface compels the latter, when the main surface rotates in a certaindirection, relatively to the body of the movable object, to rotate in the same direction relatively to the main surface.

Arrangements of the same kind are already known in non-automatical controlled rudders, but in these controlled rudders the main surface is France November 30, 1936 not entirely loose on its pivot, since it is connected by a rod system or the like to a control v member mounted on the body of the movable member and actuated by the pilot. The invention, on the contrary, is applicable exclusively to the case in which the main surface is entirely loose on its pivot and has no connection with the movable member.

In the accompanying drawings:

Fig. 1 is a diagrammatic view of the pivotally mounted main surface, the surface being shown in two positions corresponding to two directions of the relative wind acting thereon.

Fig. 2 is a graphical representation of the torque exerted by the relative wind acting on the main surface and when in the directions indicated in Fig. 1.

Fig. 3 is a diagrammatic view of the auxiliary surface which is pivoted to the main surface, the auxiliary surface being shown in two positions corresponding to the positions of the main surface shown in Fig. 1. Fig. 4 is a graphical representation of the torque exerted by the relative wind acting on the auxiliary surface and when in the directions indicated in Fig. 3.

, Fig. 5 is a diagrammatic view of an automatic stabilizing device in accordance with the present invention.

Fig. 6 is a graphical representation of the torque exerted by the relative wind acting on the surfaces of said device.

Fig. '7 is a view in elevation of a steering rudder for an aeroplane constructed in accordance with. the present invention.

Fig. 8 is a sectional elevation on the line 8-- B of Fig. 7, and

Fig. 9 is a sectional plan on the line 9-9 of Fig. '7.

-Element A.--(Fig. 1.) This element is composed of a plane I, pivoted at 2 on a fixed support, the pivot pin 2 being located in front of the center of thrust. Said element is shown in full lines for the position of unstable equilibrium it occupies when the relative wind is directed according to the arrow 1.

In Fig. 2 is shown in full lines the curve 3 representing the torques exerted by the relative wind having a direction f, on the plane I when this plane is caused, by any means whatever, to form any angle with the direction I.

In the working zone contemplated, the torques are proportional to the angles, and they are evidently of the same signs, since these torques tend to still'further space the plane i from the direction f; the assembly is therefore unstable. The angles are shown in abecissae, the torques in ordinates, and the angular coeillcient or the straisht line I is positive.

The plane i being looselypivoted at i, it the relative wind takes the direction f, forming an angle 1 with the direction I, it would be necessarytocause theplanetorotateuptotheposition shown in dotted lines in Pig. Lwhich forms. an angle i with the direction I in order that this lonsflxedsupport."l'hearmlissetinthe same direction as the relative wind having a (ll-- rectlon The plane I is; on the other hand.

connected-to the fixed support 'in such a manner that to any movement oi the arm "I relatively to said support, corresponds a" movement of the plane I relatively to the arm I. This movement must be such that the angle p passed over by the plane 5 relatively to the arm 'I is equal to no, 1: being a coeiilcient higher than -0, that is to say positive. 4

In these conditions, the device .is obviously stable,"since to any movement of rotation of the arm I relativelyto the support, the direction of the relative wind remaining 'ilxed, corresponds a torque tending to restore the whole to the initial position. Iithe wind turns to the extent of the angle 1, the device retakes'a position of equilibrium alter such a rotation (see dotted lines with the relation:.

k Inthese conditions, the curve for i= is illustrated at I in Fig; i, and the curve for a certain value of i is illustrated at II, this curve being offset to the extent of kt.

These elements A and B are known; the invention results from thecombination of these scissawhich amounts to saying that re; reaching its new, position of equilibrium-,"the'device has rotated in reverse to the rotation oi the iluid stream. V

The equation 0! ,the stability curves of the element A, which-is a straight line, as explained, is or the form y=ax+b The null ordinate point has for abscissa i x, is o (see Fig. 2) b and a are of reverse signs. The

is aplane same is true for the element 3 the curve or which is of the 'iorm I The resulting curve has therefore for equation;

I! this condition is satisfied, the device torming the subject-matter oi the invention is obtallied; illustrated in Pig. 5 and the curve of which is shown in Fig. 8.

By wayot example only, a practical embodimentof e 'syatem according to the invention willbe described hereinafter in reference to Figs. 7,8and9.

- The main rudder I isloosely'pivoted, at its front third portion at the rear oi its center oi thrmt, on a supporting tube or rudder-post 8| rilidwith the fuselage '2. This plane I is constituted by a structure having a leading'edge 83- connected by ribs 84 to a longeron ll supporting the pivotal joints of an auxiliary surface I. The main plane i is pivoted on the supporting tube 81 through the medium of the ball bearing 86 and the smooth bearing II. The supporting tube is held in position at its im elpart by the fitting as secured to the cables a connected to the'flxed part 0! the horizontal empennage, and, at its lowerparhby the ilttlng I secured by bolts to the fuselage structure.

The adjustable ball and socket member 81 is connected by a rod or link I! to the ball and socket joint 93 carried bytlielever 94 secured by bolts to the auxiliary surface, 5. The adjustment of the ball and socket member 9| is obtained by the rotation of the aileron leverkSS' carrying the same and which is rigid with the double aileron lever It; The latter is controlled by'cables ll secure'd at II and Site this aileron lever and which lead to the pilot's cock-pit. Fairings Ill and ill terminate the plane.

What I claim as myinvention and desire secure by Letters Patent is: a

1. In a stabilizer for aerial vehicles, a first pivot secured on the-vehicle, a first material surof any other connection with the vehicle and having the center of thrust in front of said first pivot in order that any change in direction of the relative wind should produce on said surface a stress which tends to cause it to rotate for increasing the angle formed-by said surface with the new direction of the wind, a second pivot secured on the rear part of said first material surface, a second material surface mounted on said second pivot and means for connecting said second material surface to said vehicle in'order that the rotation of'said first material surface shouldproduce a relative rotation in the same direction of the second material surface which then creates, under the action of the relative wind, a stress exerted on said first material surface for limiting the angle of rotation of said first surface.

2. In a stabilizer for aerial vehicles, a first pivot secured on the vehicle, a first material surface freely mounted on said first pivot, and free of any other connection with the vehicle and having the center of thrust in front of said first pivot in order that any change in direction of the relative wind should produce on said surface a stress tending to cause it to rotate for increas-' ing the angle formed by said surface with the new direction of the wind, an arm rigid with said first material surface and directed behind the latter, a second pivot mounted at the rear of said arm, a second material surface mounted on said second pivot and means for connecting said second material'surface to said vehicle in order that the rotation of said first material surface should produce a relative rotation in the same direction of the second material surface which then creates, under the action of the rela-' tive wind, a stress exerted on said first material surface and for limiting the angleof rotation of said first surface.

3. In a stabilizer for aerial vehicles, a first pivot secured on the rear part of the vehicle, a

first material surface freely mounted on said first pivot, and free of any other connection with the vehicle and having the center of thrust in front of said first pivot in order that any change in direction of the relative wind should produce on said surface a stress which tends to cause it to rotate for increasing the angle formed by said surface with the new direction of the wind, a second pivot mounted at the rear of said firstrmaterial surface, a second material surface mounted onsaid second pivot and means for connecting said second materialysurface to said vehicle in order that the rotation of said first material'surface should produce a relative rotation in the same direction of the second material surface which then creates, under the action of the relative wind, a stress exerted on said first material surface for limiting the angle of rotation of said first surface.

4. In a stabilizer for aerial vehicles, a first pivot secured on the rear part of the vehicle, a first material surface freely mounted. on said first pivot, and free of any other connection with the vehicle and having the center of thrust in front of said first pivot in order that any change in direction of the relative .wirfd should produce on said surface a stress which tends to cause it to rotate for increasing the angle formed by the said surface with the new direction of the wind, a second pivot mounted at the rear of said first material surface, a second material surface mounted on said second pivot, an arm connected to said second material surface, a link for connecting said arm to a point of said vehicle in order that the rotation of said first material surface should. produce a relative rotation in the same direction of the second material surface which then creates, under the action of the relative wind, a stress exerted on said first material surface for limiting the angle of rotation of said first surface.

5. In a stabilizer for aerial vehicles, a first pivot secured on the rear part of the vehicle, a first material surface freely mounted on said first pivot, and free of any other connection with the vehicle and having the center of thrust in front of said first pivot in order that any change in direction of the relative wind should produce on said surface a stress which tends to cause it to rotate for increasing the angle formed by the said surface with the new direction of the wind, a second pivot mounted at the rear of said first material surface, a second material surface mounted on said second pivot, an arm connected to said second material surface, a link for conof thepoint of the vehicle to which the link is connected.

' MARC, EL pours aumom. 

